Light Knock
 

Ok.... So here is one for you old timers:) Just picked up a new SVX last weekend and it seems to be a good car, but I was hopeing for some input on a few problems.
The car is a 94 Laguna Blue with 125,000mi. It seems to be in decent shape, but I have next to no info on service history:( It has a 4.44 swap done by svxfiles thats about 2 years old.
Problem #1. There is a light knock at idle. seems to come from arround the oil pan, but goes away arround 1200rpm. Do you guys think it is a rod berring, seeing that crusing at 75mph = almost 4000rpm. Or do you think that it is the oil pump? what should the oil pressure at idle? Also the engine seems to idle ok, but it shakes alot. That could just be bad engine mounts though. I cheacked the plugs, they looked good, but look like the origionals.
There were 3 codes stored in the ECU, but have not shown up since cleared. #32 right O2 sensor, #22 knock sensor right side, #56 EGR system. Do you think these could be related? This leads me to my next question.
Problem #2. All the bolts on the right side of the intake are loose, and the 2 closest to the EGR port were backing out. What is the torque specs for these bolts, and could this have been related? Should I now replace the gaskets? I should also add that I was having some problems with the MAF, but I seem to have got that sorted out.
Any help appreciated.

Im not an old timer but ill throw my $.02..

The oil filter on the car is for a 944 I believe. I do not know if the internal pressure relive valve is approved for use on our engines. Also @ that mileage a new oil pump would not hurt anything.

Inspect the knock sensors for cracking. once the plastic casing on them begins to crack I dont think they are reading as accurately. Thats when I replace mine anyway.

If the intake manifold bolts are loose that may be giving you the egr and or maf codes. a vaccum leak in the intake system can cause a few different problems. inspect the gaskets for damage. or replace them just to eliminate the possibility of problems.

Hey Eric.
Thanks for the $0.02. I changed the oil and filter already. I used 10W40 Mobile1 and purolator platinum filter. Just picked up new plugs, and will try putting them in tonight. Still get the knock. Going to try and hook up a pressure sender and guage and see if the pressure drops off at idle. It makes me wonder though, because I dont get any valve noise. Anyways, thanks for the advice.

It may be as simple as low-octane fuel. Especially as the weather warms up, the knocking from lower octane will get louder... use the highest octane you can get in your area... and even if you're curious dump a container of octane booster into your fuel tank to make sure any existing low-octane fuel has been "boosted".

I know I saw the same problem with my 94; the previous owner had filled it with 87 octane frequently and the stealership I bought it from "filled it up for me" when I picked up the car... of course with 87. I drove it for a day before I took it to the gas station, topped it off with 93 octane AND dumped a bottle of booster into the tank. The knocking vanished and I never heard it again.

Also, be aware that it may not necessarily be knocking. Use a stethoscope to track down the source properly. I thought I had a knock until I did this, then found that one of my fuel injectors was causing a very "knock-like" noise at idle. Replaced injector, no problems.

As an aside, I know all the nearby stations I can get 93 octane... most of the cheapo stations sell 91!

Did you hook up the pressure gauge? what was the reading?

how do the knock sensors look?

It only does it at idle. if the idle speed is to low then the oil pump may not be turning fast enough or is worn. I would think a rod bearing would be constant at all rpms.

p.s.
Can you please respond to your pms?